Process and apparatus for forming casts



30, 1920. 2 SHEETS-SHEET l.

A. G. BERGMAN. PPocPss AND APPARATUS PoP mamme cAss. APPLICATION lFILEDOCT. I5, i919.

Patented Mar,

INVENTOR WITNESS A. G. BERGMAN.

PROCESS AND APPARATUS FOR FORMING CASTS. APPLICATION FILED OCT. I5,I9I9.

1,335,47@ Y Patented Main 30, 1920..

2 SHEETS-SHEET 2.

' UNrrED 'saafrEs PATENT oEEroE.

AXEL e. BEEGMAN,

TRUSTEE,

To all whom t may concern:

Be it known that 1, AXEL G. BERGMAN, a subject of the` King of Sweden,residing in the borough of Manhattan, city, county, and State of NewYork, have invented certain new and useful Improvements in Processes andApparatus for Forming Casts, of which the following is a specification.y,

This invention relates toa process and 'apparatus for forming plaster orother similar casts, and is more particularly directed to the formationof a mold or matrix to be l rast as a guide for fashioning the socket ofSuch efforts have, however, been the limb.

since the casts have only partly successful,

been taken of the stump by simply iminers- Y ingvit in a solution ofplaster of Paris, or similar substance, and permitting the latter toset. This produces a correct matrix of the limb as it normally eXists,but fails to take into account the fact that when the leg is used thefull weight of the user is borne by the artificial limb in walking, withthe result that the stump is put under a pressure which changes itsAform very materially. i

Under such pressure the muscular or fatty portions of the limb yield,with the eect that the bony sections are pressed against the socket andcontinued use becomes painful or impossible.

Accordingto the present invention I^pro vide a process and apparatus formaking molds or casts which will conform to the shape of the stump whilethe latter is under substantially thev same pressure as is experiencedin use. The result is vthat the socket of the artificial limbwhenconstructed to conform to the cast thus made perfectly fits the stumpunder conditions of actual service. so that pain or discomfort in the.use of the limb is avoided:

' The. invention may be practised in several ways, but I prefer forsimplicity to adopt a 'I prefer to OF NEW YORK, N. Y., ASSIGNOR, TOLEYG-RAND Sc COMPANY, INC.,

0F NEW YORK, N. Y., .A CORPORATION OF NEW JERSEY.

PROCESS AND APPARATUS FOR FORMING CASTS.

Specification of Letters Patent. Patented B131. 30, 192,0. Applicationfiled October 15., i919. Serial No. 330,717. i l

method which enables the person whose cast is to be-taken to himselfintroduce the necessary pressure. Thus according to 'the preferred formI provide a receptacle of suitable size and shape in which the plasterof Paris, or other molding material, is introduced in fluid form, and Iconfine the fluid substance against escapewhile the stump is introducedwithin it, the user placing his weight, or a considerable part thereof,onto the stump, soth'at it is lput under-a pressure substantiallysimilar to the pressure which vit will afterward bear when theartificial limb is worn. The invention includes ce1'- tain otherfeatures of improvement which will hereinafter be more fully described.

Referring to the drawings which illustrate one form ofthe invention,

Figure 1 is a diametrcal section vof an y appropriate form of receptaclefor use in practlsing the present lnvention.

Fig. 2 is a diagrammatical view of a limb equipped for the molding`operation.

Fig. 3 is a view during the molding operation, the receptacle beingshown in diametrical section.

Fig. 4 is a plan view of the ing I prefer to employ.

Fig. 5 is a plan of a rubber disk which is useful in practising theinvention.

Referring to the drawing, cate a suitable mold receptacle which for thepresent purpose isbest elongated to an extent to receive the longeststump which is designed to bev molded. It is preferably tapered inwardlyfrom top to bottom, and is form of stockkbest provided with-a liningmember B which may consist of a sheet of metal preferably withunattached edges, so that it maybe sprung apart upon removal from thereceptacle A. It is best to provide a lower lining disk C. Within themetallic lining arrange a flexible lining, or bag, which is best made ofwater-proof material, such asrubber sheeting or suitably prepared paper.The object of this lining is to practically contain the plaster of'Paris mixture, thereby avoiding thesoiling of the mold proper oradherence `of vplaster of Paris thereto. Thereccptacle A ispreferablypro-V vided with a bead or lip A', both for stiifening purposes and alsoto provide a ,shoulder around which the top of the flexible llnlng'D letA indii band G.

In Fig. 2 I have shown the stump and l limb properly prepared for thecasting operation in advance of the immersion of the stump in themolding material. I prefer to incase'the stump preferably up to ltheknee in the form of stocking indicated by the letter F in Fi 2 and shownattached? in Fig/1. It wil be noted from Fig. 4 that the upper part ofthe stocking 1*" is enlarged to an extent which is out of proportion tothe limb forl a purpose to be shortly described. lOver the stocking andarranged at about the knee is a rubber, or other 'suitable disk-likesheet, such as is indicated by tlie reference letter E, and which isshown de tached in Fig. 5. The disk E is provided Ythe dis E is thenturned downwardly and with a central aperture of smaller dimen` sionsthan the knee so that it hugs the knee ver closely 'and withconsiderable tension.

hen the stump has been suitably prepared as shown at Fig. 2, the mixtureof plaster of Paris, or other molding material, is then made, and inthecase of plaster of Paris I prefer to mix the material with water to theconsistency of a heavy creamor. light batter.

AThe stump is then immersed in theliquid and the edges ofthe disk E arebrought over the top of the receptacle A and fastened down fairlytightly -by the use of some tension member,- such .as the rubber stripH. Thatpart of the stockin which -is enlarged and `lies above stretchedover 'the topof the disk and the bead of the receptacle, and is' alsofastened down by a suitable tension member, such as the rubber strip I.

The person whose cast is to be taken then preferably stands (in case onelimb is still intact) and places his weight, .or a considerableproportion thereof, on the limb which has been partly amputated. Themold is elevated if necessary by the vuse of a stool or other supportvuntil it is approximately the right heightso that` when pressure is lput upon the stump ythe user will be substantially erect.' l

The result of the weight of the user being placed upon the stump is thatthe Y latter descends farther into the a position which" is roughlyindicated in dotted lines at L in Fig. 3 to the position shown 1n fulllines. This displaces a considerable quantity of the molding fluid whichtends' to overflow the mold. This is resisted, h owever, by the rubberdisk E so that the parts assume .substantially the position of Flg. 3.

pressure,

vprocess may be mold passing from Care should, of course, be takeninitiallyv to see-that there is sufficient level of the molding fluid toreach the top of the mold, and even beyond, when the weight is placedupon the limb. When the proper pressure is reached it is maintaineduntil the mol-ding `fluid hardens and sets.

for themselves in the matrix. As the tension of the fluid is uniform on.all parts a very precisev and comfortable fit. of the subsequentlyformed socket is assured.

The precise degree of weight which` is placed upon the stump during themolding operation will differ somewhat withv different individuals, vbut-the best results are usually found when all the weight is placed uponthe stump which the user can conveniently and comfortably stand. 'Thiswill usually be 'considerably over one half the weight of the 'user andsometimes nearly allv the weight. AIghave found in practice that it isadvisable to apply vaseline, or other grease,`to the stump beforeplacing it in the stocking and` also to dampen the stocki-ng well withwater. If any leakage takes place in the plaster of Paris this -willsoon stop on account of the'hardening of the latter. When theplaster ofParis attains some degree of hardness the pressure upon the stump canberelieved, but it should be kept in place until the plaster ofvl-arisvhas fully hardened.

pleted, care should be taken i-n removing the stump. It is advisable tovgently reduce the bring the stump into the passive condition and to workthe muscles slightly to help introduce slightly by the vfinger so as toassist in this operation, whereupon the stump-may be easily withdrawn. v

4 l air between the stump andv g 'the mold. -The muscles may becompressed It will be understood that the specific very considerablyvaried without departing from the invention so long as the mold is madeunder pressure, shown asfone adapted for the purpose is susceptible towide variation.

It will be also understood, of course, that after the matrix is made, aplaster, or other cast, will be taken and thatlthe socket of theartificial leg will be fabricated as a facsimile of the matrix of thestump obtained by the cast.. This can .be done by molding papier mch andthat the form of apparatus is merely and by the use of the replica' isoWhile the latter is under pressure.

fluid.

2. A process of forming a replica of a stump in the production ofartificial limbs, comprising forming a matrix of the'stump while thelatter is under a pressure approximating that which the stump is underin the use of the completed limb. 7

3. A process of forming a replica of a stump in the production ofartificial limbs, comprising forming a matrix of the stmnp and duringthe matrix forming operation placing the stump under a pressure byvforcing the latter into theV matrix forming 4:. A process of forming areplica of a stump m thee-'production of artificial limbs,

comprising placing tlie'matrix forming fluid in a. mold receptacle,introducing the stump therein, pressing inwardly upon the stump andconfining the fluid against escape.

5. A process of forming a replica of' a. stump in the production ofartificial limbs, comprising placing the matrix forming fluid in a moldreceptacle, introducing the stump therein, pressing inwardl)Y upon thestump and confining the fluid against escape by a flexible connectionbetween the limb and the top of the receptacle.

6. An apparatus for making matrices of' a stump or the like,

of forming a replica of a comprising a receptable4 Jfor containing themolding material, an opening for the introduction of the stump and meansfor placing the molding material under pressure.

7. An apparatus for making matrices of a stump or the like, comprising areceptacle for containing the molding material, an

" opening for theintroduction of the stump Aand means for placing themolding material under pressure, said means comprising a flexible 'diskthrough which the stump passes.

8. An apparatus for making matrices of' a stump or the like, comprisinga receptacle for containing the molding n'iaterial, and a :flexible diskhaving an aperture through it. 9,'An apparatus for making matrices of' astump or the like, comprising a receptacle forcontaining the moldingmaterial, and

a flexible lining member Within the mold and a flexible disk for the topof the mold having an aperture through it.

10. An apparatus for making matrices of a stump or the like, comprisinga receptacle for containing the molding material, a separable metalliclining Afor said receptacle and a flexible disk 'for the top of saidreceptacle.

` 11. An apparatus for making matrices of a stump or the like,comprising a receptacle 'for containing the molding material, aseparable metallic lining for said receptacle. flexible lining withinsaid metallic lining .and a flexible disk for fitting over the mold.

in Witness whereof have hereunto signed my name.

AXEL G. BERGMAN;

